Obviously ζωὴ carries a theological weight that ψυχὴ does not in John's gospel, but I'm curious how they are used outside of it. Is "life" an appropriate translation for both? Are they essentially synonymous? Are there differences in their connotation?

According to Kittel, ψυχὴ is related to "ψύχω “to blow (to cool)” and ψῦχος “cold,” is on this view the vital force which resides in the members and which comes to expression especially in the breath." When you breath your last, you lose it.

On the other hand "ζωή (ζῆν) denotes in Greek the physical vitality of organic beings, animals, men and also plants. Life is understood, not as a thing, but as vitality, as the nature or manner which characterizes all living creatures as such. Hence ζωή cannot be used in the plural."

I think some of the Greek words got mixed up... ψυχὴ (psukhe) is what is translated as "soul/person/mind/etc." and refers to our own lives. ζωὴ (zoe) is translated as "life/living" and refers to the concept of life itself.
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Noam SiennaMar 8 '13 at 16:12